This paper analyses and discusses the usability aspect of the text-based CAPTCHA in terms of response time and success in solving the CAPTCHA on tablet computers. The response time is the time spent by the user to find a solution to the CAPTCHA. The analysis is separately conducted on text-based CAPTCHA with only text and numbers. Then, the results are compared and the differences in response time and success in solving the two types of CAPTCHA are underlined. This is accomplished by asking 125 Internet users to solve the text-based CAPTCHA on the tablet computer. Their gender, age, education level, Internet experience, response time and success in solving two types of text-based CAPTCHA are collected in a dataset. Then, advanced statistical analysis by association rule mining is performed. It shows the dependence of the response time and success in solving the CAPTCHA on co-occurrence of gender, age, education level and Internet experience and the strength of this dependence by support, confidence and lift measures. This study provides relevant information for designing new CAPTCHAs which may be more accustomed to specific types of Internet users.

中文翻译：

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探索基于文本的验证码在平板电脑上的可用性

本文分析和讨论了基于文本的验证码在响应时间和在平板电脑上解决验证码的成功率方面的可用性方面。响应时间是用户寻找验证码解决方案所花费的时间。分析是在基于文本的 CAPTCHA 上单独进行的，只有文本和数字。然后，对结果进行比较，并强调响应时间和解决两种验证码成功率的差异。这是通过要求 125 名互联网用户在平板电脑上解决基于文本的 CAPTCHA 来实现的。他们的性别、年龄、教育水平、互联网经验、响应时间和解决两种基于文本的 CAPTCHA 的成功率都被收集在一个数据集中。然后，通过关联规则挖掘进行高级统计分析。它通过支持、置信和提升措施显示了响应时间和解决 CAPTCHA 成功对性别、年龄、教育水平和互联网经验的共现的依赖性以及这种依赖性的强度。本研究为设计可能更适合特定类型互联网用户的新 CAPTCHA 提供了相关信息。